Solar invoicing software has to solve a problem no other trade has: on a financed job you do not really invoice the homeowner at all, you submit milestone packages to a lender and wait for a disbursement. On a cash job you invoice normally, in stages, against equipment you already paid for. Most installers therefore need a tool that tracks lender milestones (notice to proceed, installation, activation) alongside conventional invoices and payments, because those two money flows run on completely different clocks.
Key takeaways
- On financed jobs your "invoice" is a document package. Palmetto's installer guides for its Solar Energy Plan define NTP (notice to proceed), M1 (installation), and M2 (activation), with M1 and M2 each requiring a formal submitted package before funding moves.
- Funding has shifted later. Installer-facing coverage in 2026 notes lenders pushing more of the payout toward the PTO milestone rather than paying out fully at installation, which lengthens the gap between spending on equipment and getting paid.
- Cash jobs need real progress invoicing: a deposit, a payment around equipment delivery, a payment at install completion, and a final balance after inspection or PTO.
- Equipment is roughly 50 to 60 percent of system price and distributor terms are commonly NET30, per Greentech Renewables' cash flow series, so a late milestone lands directly on your credit line.
- California caps home improvement down payments (solar included) at 10 percent of the contract or $1,000, whichever is less, under CSLB rules, so deposit templates are not a free choice.
Why solar invoicing is a milestone problem, not an invoice problem
Solar invoicing breaks the assumption behind every generic invoicing app: that you send a bill to the person who owes you money. On a financed residential install, the homeowner signs a loan and the lender becomes your payer. You get paid when you prove a milestone happened, with photos, signed documents, permit records, and inspection or utility paperwork attached. Miss one document and the disbursement sits still while your distributor invoice comes due.
That means the useful measure for a solar company is not "invoices sent" but "milestones submitted and funded." Software that only shows an accounts receivable aging report tells you almost nothing, because on a financed job there is no overdue customer to chase, only a package you have not completed. Our cross-trade roundup of the best invoicing and payment collection software for contractors covers the general field; this page is about the solar-specific layer that sits on top of it.
Cash jobs and financed jobs are two different billing systems
Solar companies run both flows at once, and mixing them in one loose process is how margin disappears. The difference is worth spelling out because your software has to model both.
| Cash job | Financed job | |
|---|---|---|
| Who pays you | The homeowner | The lender or TPO provider |
| What triggers payment | An invoice you send at an agreed stage | A milestone package you submit and the lender approves |
| What you track | Invoice status, balance, overdue days | Milestone status, missing documents, days in stage |
| Equipment funding | Your working capital or your deposit | Sometimes distributor direct pay from the lender |
| Collection risk | Homeowner does not pay | Package is incomplete, or the lender changes terms |
| Price shown | Cash price | Cash price plus the dealer fee, which 2026 lender comparisons put anywhere from about 10 to 30 percent of the loan |
The dealer fee is the piece owners most often mishandle in their books. Lender comparison write-ups published in 2026 (NuWatt Energy, IntegrateSun) describe fees commonly in the 15 to 30 percent range, with roughly 22 percent cited as typical on residential loans. It is a real cost of the sale even though it never appears on a homeowner invoice, so record it against the job or your job costing will flatter every financed deal. Our breakdown of dealer fees in contractor financing walks through the math.
One 2026 change affects both flows: the residential Section 25D tax credit expired on December 31, 2025, so cash and loan buyers no longer get 30 percent back from the IRS. Any proposal or invoice template still showing a "net cost after tax credit" line for a residential customer is now wrong, and leaving it in place is a liability.
Lender milestone disbursements: NTP, M1, and M2
Lender milestone disbursements are staged payments released as a project reaches defined checkpoints, each requiring evidence. Names vary by lender, but Palmetto's published installer documentation for its Solar Energy Plan is a clear public example of the pattern.
| Milestone | What it means | Typical evidence |
|---|---|---|
| NTP (notice to proceed) | Contract package complete, you may order and install | Executed contract, design, site survey, credit approval. Palmetto grants NTP automatically once requirements are met |
| M1 (installation) | System physically installed | Install photos, final design as built, permit, sign-offs. Requires a formal submitted package |
| M2 (activation) | System energized and approved to operate | Inspection sign-off and utility PTO documentation. Also a formal submitted package |
Two operational facts matter more than the labels. First, lenders have been moving the weight of the payout later. Installer guidance published through 2026 describes structures where full payment historically arrived around M1 and M2 but now leans on the PTO milestone, which can sit weeks behind installation while a utility processes interconnection. Second, the milestone is only as fast as your document collection. A crew that finishes an install on Friday and uploads photos the following Wednesday has voluntarily added five days to its own funding cycle.
Practical rule: treat every milestone submission as an invoice with a due date and an owner. If your platform cannot show projects sitting at M1 with missing documents, sorted by days waiting, you will find those jobs only when your bank balance drops.
Must-have invoicing features for solar contractors
Solar invoicing software earns its place on a short list of features. Generic tools cover the bottom half of this table well and the top half not at all.
| Feature | Why solar installers specifically need it |
|---|---|
| Milestone tracking with document checklists | Funding depends on complete packages at NTP, M1, and M2, not on an invoice being sent |
| Per-job funding view (expected vs received) | Shows what the lender still owes on each project and what is blocking it |
| Dealer fee recorded as job cost | Financed jobs look more profitable than they are until the fee is booked against the job |
| Progress invoicing for cash jobs | Deposit, equipment, install, and final balance billed from one job record |
| Change order and adder handling | Panel upgrades, main panel upgrades, and roof work change the contract total mid-project |
| ACH plus card payments with fee controls | At solar ticket sizes, card fees on a final balance are hundreds of dollars |
| Equipment and PO cost capture | Panels and inverters run roughly half the system price and are paid on distributor terms |
| Accounting sync | Keeps milestone receipts, deposits, and equipment bills matching your books |
What solar invoicing software costs in 2026
There is no large market of solar-only invoicing products. In practice installers assemble it from three layers plus the lender portal. Pricing below reflects published or commonly reported figures as of mid-2026.
| Layer | Examples | Cost (mid-2026) | What it covers |
|---|---|---|---|
| Solar platform | OpenSolar, Aurora Solar | OpenSolar free for installers; Aurora residential tiers from around $159 per month per seat per 2026 comparisons | Design, proposals, pipeline, and in OpenSolar's case built-in invoicing and payments |
| Field service / invoicing | Jobber and similar | Jobber from $29 per month solo, team plans up to $599 per its published pricing | Quotes, progress invoices, deposits, card and ACH payments, scheduling |
| Accounting | QuickBooks Online | $38 to $275 per month per Intuit's 2026 pricing | Progress invoicing on estimates, job costing, distributor bills, financial reporting |
| Lender portal | GoodLeap, Palmetto LightReach, EverBright, others | No subscription; dealer fees commonly 10 to 30 percent of the financed amount | Milestone submission and disbursement on financed jobs |
| ERP (larger installers) | NetSuite-based solar suites | Quote-based, well above the tools above | Milestone billing, revenue recognition, inventory, multi-entity reporting |
Processing fees deserve their own line in the budget. At a common rate near 2.9 percent plus about $0.30 per card transaction, a $30,000 cash system billed on a card costs roughly $870 in fees, which is often more than a full year of software. Take cards for deposits and small adders, and steer five-figure balances to ACH or check. Our comparison of accounting software for contractors covers which tier actually handles job costing at this size.
How to evaluate solar invoicing software
- Split last year's revenue between cash and financed. Heavy financed volume means milestone tracking is the deciding feature. Heavy cash volume means progress invoicing and deposit rules matter more.
- Run one real financed job through the trial. Contract to NTP to M1 to M2, with the actual document list. If the tool cannot represent the milestones, you will keep the real tracking in a spreadsheet anyway.
- Ask for the funding report in the demo. Expected lender payments by project and milestone, with days in stage. Ten seconds to produce it, or the vendor does not understand solar.
- Check where the dealer fee lands. It should be recordable as a cost on the job, not silently ignored so financed jobs report inflated margin.
- Confirm deposit compliance for your states. California limits home improvement down payments to 10 percent or $1,000, whichever is less, under CSLB rules; other states vary. The tool must bill your legal structure without workarounds.
- Test the accounting sync and the field upload. Milestone receipts, homeowner payments, and distributor bills must land against the right job, and crews must be able to attach install photos from the phone at the site.
Common invoicing mistakes solar contractors make
- Treating a milestone package as paperwork instead of an invoice. It is the invoice. Give it a due date and an owner, and measure days from install to submission.
- Leaving the dealer fee out of job costing. A 22 percent fee on a $30,000 financed system is about $6,600 of cost that never shows on a homeowner invoice.
- Running all volume through one lender. Mosaic's 2025 collapse froze milestone payments for installers who had no second option. Keep a live alternative, and see our comparison of Hearth vs Sunlight, Mosaic, and EnerBank plus the Hearth vs GoodLeap fee breakdown.
- Billing cash jobs in two chunks. A deposit and a final payment means you finance the equipment yourself on NET30 distributor terms. Add a stage at delivery or install completion.
- Eating card fees on five-figure final balances. Hundreds of dollars per job, avoidable by routing large payments to ACH.
- No visibility of what the lender owes. If you cannot state today's total outstanding lender funding, you cannot forecast next month's payroll. The math in our piece on the true cost of financing decisions applies as much to tracking the money as to whether you offer it.
Frequently asked questions
Is there dedicated solar invoicing software?
Not really as a standalone category: most installers combine a solar platform, a field service or invoicing tool, and an accounting system, with lender portals handling financed disbursements. OpenSolar includes invoicing and payments in its free installer product, general tools like Jobber handle quotes and progress invoices, and larger installers move milestone billing into an ERP such as a NetSuite-based solar suite.
What do M1 and M2 mean on a solar loan?
M1 generally means installation and M2 means activation, the point where the system is energized and approved to operate, with NTP (notice to proceed) coming before both. Palmetto's installer guides show the pattern clearly: NTP is granted automatically once requirements are met, while M1 and M2 each require a formal submitted document package before funding is released. Exact names and evidence lists differ by lender, so build your checklist from your own lender's documentation.
When does the installer actually get paid on a financed job?
Payment follows approved milestone packages rather than an invoice date, and the timing has moved later: installer-facing guidance in 2026 describes lenders leaning more on the PTO milestone instead of paying out fully at installation. Because utility interconnection and PTO can take weeks after the panels are on the roof, plan working capital around the PTO date, not the install date.
How should I invoice a cash solar job?
Use progress invoicing with at least three stages: a deposit at signing, a payment when equipment is delivered or the install starts, and the balance after installation or final inspection. Equipment is roughly 50 to 60 percent of system price on typically NET30 distributor terms per Greentech Renewables' cash flow series, so a two-payment structure makes you the bank for the hardware.
How big a deposit can I take on a solar contract?
It depends on the state, and California is the strict case: CSLB rules cap home improvement down payments, solar included, at 10 percent of the contract price or $1,000, whichever is less. Many other states set no explicit cap, so confirm your licensing board's rules before standardizing a deposit percentage across markets.
Should the dealer fee appear on the homeowner's invoice?
No, the dealer fee is charged to you by the lender, so it belongs in your job costing rather than on the customer's document, which is exactly why so many installers forget to record it. What the homeowner sees is a financed price higher than your cash price, and being straight about that difference when they ask is better than being caught adjusting it later. Our explainer on how 0 percent APR financing actually works covers the same buy-down mechanics.
Next step: pull last quarter's financed jobs and measure the days from install completion to milestone submission, then to funding. That single number tells you whether your problem is software, documentation discipline, or the lender, and it is the only honest way to judge a tool before you buy it. If your pipeline tracking is the weak point rather than the billing, start with our contractor CRM buyer's guide instead.